TMEM8A

TMEM8A (Transmembrane Protein 8A) is a Protein Coding gene. It is involved in the lipid remodeling steps of GPI-anchor maturation. Lipid remodeling steps consist in the generation of 2 saturated fatty chains at the sn-2 position of GPI-anchor proteins (GPI-AP). It has phospholipase A2 activity that removes an acyl-chain at the sn-2 position of GPI-anchors during the remodeling of GPI. It is required for the shedding of the GPI-AP TDGF1, but not CFC1, at the cell surface. Shedding of TDGF1 modulates Nodal signaling by allowing soluble TDGF1 to act as a Nodal coreceptor on other cells (PubMed:27881714). It is also indirectly involved in the translocation of RAC1 from the cytosol to the plasma membrane by maintaining the steady state amount of CAV1-enriched plasma membrane subdomains, stabilizing RAC1 at the plasma membrane (PubMed:27835684). In contrast to myomaker (TMEM8C), it has no fusogenic activity (PubMed:26858401). An important paralog of TMEM8A is TMEM8B.

Full Name

Transmembrane Protein 8A

Function

Involved in the lipid remodeling steps of GPI-anchor maturation. Lipid remodeling steps consist in the generation of 2 saturated fatty chains at the sn-2 position of GPI-anchor proteins (GPI-AP). Has phospholipase A2 activity that removes an acyl-chain at the sn-2 position of GPI-anchors during the remodeling of GPI. Required for the shedding of the GPI-AP TDGF1, but not CFC1, at the cell surface. Shedding of TDGF1 modulates Nodal signaling by allowing soluble TDGF1 to act as a Nodal coreceptor on other cells (PubMed:27881714).
Also indirectly involved in the translocation of RAC1 from the cytosol to the plasma membrane by maintaining the steady state amount of CAV1-enriched plasma membrane subdomains, stabilizing RAC1 at the plasma membrane (PubMed:27835684).
In contrast to myomaker (TMEM8C), has no fusogenic activity (PubMed:26858401).

Biological Process

Lipid metabolic process

Cellular Location

Cell membrane
Lysosome membrane

Topology

Extracellular: 35-545
Helical: 546-566
Cytoplasmic: 567-568
Helical: 569-589
Extracellular: 590-605
Helical: 606-626
Cytoplasmic: 627-629
Helical: 630-650
Extracellular: 651-653
Helical: 654-674
Cytoplasmic: 675-690
Helical: 691-711
Extracellular: 712-717
Helical: 718-738
Cytoplasmic: 739-771

PTM

Glycosylated.